vp9: allocate 'b', 'block/uvblock' and 'eob/uveob' dynamically.
[ffmpeg.git] / libavcodec / ac3dec.c
index 1656a4c..9afc54d 100644 (file)
@@ -7,20 +7,20 @@
  * Copyright (c) 2007-2008 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
  * Copyright (c) 2007 Justin Ruggles <justin.ruggles@gmail.com>
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <math.h>
 #include <string.h>
 
+#include "libavutil/channel_layout.h"
 #include "libavutil/crc.h"
+#include "libavutil/downmix_info.h"
+#include "libavutil/opt.h"
+#include "bswapdsp.h"
 #include "internal.h"
 #include "aac_ac3_parser.h"
 #include "ac3_parser.h"
 #include "ac3dec.h"
 #include "ac3dec_data.h"
-
-/** Large enough for maximum possible frame size when the specification limit is ignored */
-#define AC3_FRAME_BUFFER_SIZE 32768
+#include "kbdwin.h"
 
 /**
  * table for ungrouping 3 values in 7 bits.
@@ -45,7 +47,6 @@
  */
 static uint8_t ungroup_3_in_7_bits_tab[128][3];
 
-
 /** tables for ungrouping mantissas */
 static int b1_mantissas[32][3];
 static int b2_mantissas[128][3];
@@ -66,16 +67,6 @@ static const uint8_t quantization_tab[16] = {
 static float dynamic_range_tab[256];
 
 /** Adjustments in dB gain */
-#define LEVEL_PLUS_3DB          1.4142135623730950
-#define LEVEL_PLUS_1POINT5DB    1.1892071150027209
-#define LEVEL_MINUS_1POINT5DB   0.8408964152537145
-#define LEVEL_MINUS_3DB         0.7071067811865476
-#define LEVEL_MINUS_4POINT5DB   0.5946035575013605
-#define LEVEL_MINUS_6DB         0.5000000000000000
-#define LEVEL_MINUS_9DB         0.3535533905932738
-#define LEVEL_ZERO              0.0000000000000000
-#define LEVEL_ONE               1.0000000000000000
-
 static const float gain_levels[9] = {
     LEVEL_PLUS_3DB,
     LEVEL_PLUS_1POINT5DB,
@@ -88,17 +79,14 @@ static const float gain_levels[9] = {
     LEVEL_MINUS_9DB
 };
 
-/**
- * Table for center mix levels
- * reference: Section 5.4.2.4 cmixlev
- */
-static const uint8_t center_levels[4] = { 4, 5, 6, 5 };
-
-/**
- * Table for surround mix levels
- * reference: Section 5.4.2.5 surmixlev
- */
-static const uint8_t surround_levels[4] = { 4, 6, 7, 6 };
+/** Adjustments in dB gain (LFE, +10 to -21 dB) */
+static const float gain_levels_lfe[32] = {
+    3.162275, 2.818382, 2.511886, 2.238719, 1.995261, 1.778278, 1.584893,
+    1.412536, 1.258924, 1.122018, 1.000000, 0.891251, 0.794328, 0.707946,
+    0.630957, 0.562341, 0.501187, 0.446683, 0.398107, 0.354813, 0.316227,
+    0.281838, 0.251188, 0.223872, 0.199526, 0.177828, 0.158489, 0.141253,
+    0.125892, 0.112201, 0.100000, 0.089125
+};
 
 /**
  * Table for default stereo downmixing coefficients
@@ -135,7 +123,7 @@ static av_cold void ac3_tables_init(void)
 
     /* generate table for ungrouping 3 values in 7 bits
        reference: Section 7.1.3 Exponent Decoding */
-    for(i=0; i<128; i++) {
+    for (i = 0; i < 128; i++) {
         ungroup_3_in_7_bits_tab[i][0] =  i / 25;
         ungroup_3_in_7_bits_tab[i][1] = (i % 25) / 5;
         ungroup_3_in_7_bits_tab[i][2] = (i % 25) % 5;
@@ -143,13 +131,13 @@ static av_cold void ac3_tables_init(void)
 
     /* generate grouped mantissa tables
        reference: Section 7.3.5 Ungrouping of Mantissas */
-    for(i=0; i<32; i++) {
+    for (i = 0; i < 32; i++) {
         /* bap=1 mantissas */
         b1_mantissas[i][0] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][0], 3);
         b1_mantissas[i][1] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][1], 3);
         b1_mantissas[i][2] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][2], 3);
     }
-    for(i=0; i<128; i++) {
+    for (i = 0; i < 128; i++) {
         /* bap=2 mantissas */
         b2_mantissas[i][0] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][0], 5);
         b2_mantissas[i][1] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][1], 5);
@@ -161,65 +149,60 @@ static av_cold void ac3_tables_init(void)
     }
     /* generate ungrouped mantissa tables
        reference: Tables 7.21 and 7.23 */
-    for(i=0; i<7; i++) {
+    for (i = 0; i < 7; i++) {
         /* bap=3 mantissas */
         b3_mantissas[i] = symmetric_dequant(i, 7);
     }
-    for(i=0; i<15; i++) {
+    for (i = 0; i < 15; i++) {
         /* bap=5 mantissas */
         b5_mantissas[i] = symmetric_dequant(i, 15);
     }
 
     /* generate dynamic range table
        reference: Section 7.7.1 Dynamic Range Control */
-    for(i=0; i<256; i++) {
+    for (i = 0; i < 256; i++) {
         int v = (i >> 5) - ((i >> 7) << 3) - 5;
         dynamic_range_tab[i] = powf(2.0f, v) * ((i & 0x1F) | 0x20);
     }
 }
 
-
 /**
  * AVCodec initialization
  */
 static av_cold int ac3_decode_init(AVCodecContext *avctx)
 {
     AC3DecodeContext *s = avctx->priv_data;
+    int i;
+
     s->avctx = avctx;
 
-    ac3_common_init();
+    ff_ac3_common_init();
     ac3_tables_init();
     ff_mdct_init(&s->imdct_256, 8, 1, 1.0);
     ff_mdct_init(&s->imdct_512, 9, 1, 1.0);
     ff_kbd_window_init(s->window, 5.0, 256);
-    dsputil_init(&s->dsp, avctx);
+    ff_bswapdsp_init(&s->bdsp);
+    avpriv_float_dsp_init(&s->fdsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
+    ff_ac3dsp_init(&s->ac3dsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
+    ff_fmt_convert_init(&s->fmt_conv, avctx);
     av_lfg_init(&s->dith_state, 0);
 
-    /* set bias values for float to int16 conversion */
-    if(s->dsp.float_to_int16_interleave == ff_float_to_int16_interleave_c) {
-        s->add_bias = 385.0f;
-        s->mul_bias = 1.0f;
-    } else {
-        s->add_bias = 0.0f;
-        s->mul_bias = 32767.0f;
-    }
+    avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
 
     /* allow downmixing to stereo or mono */
-    if (avctx->channels > 0 && avctx->request_channels > 0 &&
-            avctx->request_channels < avctx->channels &&
-            avctx->request_channels <= 2) {
-        avctx->channels = avctx->request_channels;
-    }
+    if (avctx->channels > 1 &&
+        avctx->request_channel_layout == AV_CH_LAYOUT_MONO)
+        avctx->channels = 1;
+    else if (avctx->channels > 2 &&
+             avctx->request_channel_layout == AV_CH_LAYOUT_STEREO)
+        avctx->channels = 2;
     s->downmixed = 1;
 
-    /* allocate context input buffer */
-    if (avctx->error_recognition >= FF_ER_CAREFUL) {
-        s->input_buffer = av_mallocz(AC3_FRAME_BUFFER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
-        if (!s->input_buffer)
-            return AVERROR_NOMEM;
+    for (i = 0; i < AC3_MAX_CHANNELS; i++) {
+        s->xcfptr[i] = s->transform_coeffs[i];
+        s->dlyptr[i] = s->delay[i];
     }
 
-    avctx->sample_fmt = SAMPLE_FMT_S16;
     return 0;
 }
 
@@ -234,7 +217,7 @@ static int ac3_parse_header(AC3DecodeContext *s)
     int i;
 
     /* read the rest of the bsi. read twice for dual mono mode. */
-    i = !(s->channel_mode);
+    i = !s->channel_mode;
     do {
         skip_bits(gbc, 5); // skip dialog normalization
         if (get_bits1(gbc))
@@ -247,19 +230,33 @@ static int ac3_parse_header(AC3DecodeContext *s)
 
     skip_bits(gbc, 2); //skip copyright bit and original bitstream bit
 
-    /* skip the timecodes (or extra bitstream information for Alternate Syntax)
-       TODO: read & use the xbsi1 downmix levels */
-    if (get_bits1(gbc))
-        skip_bits(gbc, 14); //skip timecode1 / xbsi1
-    if (get_bits1(gbc))
-        skip_bits(gbc, 14); //skip timecode2 / xbsi2
+    /* skip the timecodes or parse the Alternate Bit Stream Syntax */
+    if (s->bitstream_id != 6) {
+        if (get_bits1(gbc))
+            skip_bits(gbc, 14); //skip timecode1
+        if (get_bits1(gbc))
+            skip_bits(gbc, 14); //skip timecode2
+    } else {
+        if (get_bits1(gbc)) {
+            s->preferred_downmix       = get_bits(gbc, 2);
+            s->center_mix_level_ltrt   = get_bits(gbc, 3);
+            s->surround_mix_level_ltrt = av_clip(get_bits(gbc, 3), 3, 7);
+            s->center_mix_level        = get_bits(gbc, 3);
+            s->surround_mix_level      = av_clip(get_bits(gbc, 3), 3, 7);
+        }
+        if (get_bits1(gbc)) {
+            s->dolby_surround_ex_mode = get_bits(gbc, 2);
+            s->dolby_headphone_mode   = get_bits(gbc, 2);
+            skip_bits(gbc, 10); // skip adconvtyp (1), xbsi2 (8), encinfo (1)
+        }
+    }
 
     /* skip additional bitstream info */
     if (get_bits1(gbc)) {
         i = get_bits(gbc, 6);
         do {
             skip_bits(gbc, 8);
-        } while(i--);
+        } while (i--);
     }
 
     return 0;
@@ -273,14 +270,15 @@ static int parse_frame_header(AC3DecodeContext *s)
     AC3HeaderInfo hdr;
     int err;
 
-    err = ff_ac3_parse_header(&s->gbc, &hdr);
-    if(err)
+    err = avpriv_ac3_parse_header(&s->gbc, &hdr);
+    if (err)
         return err;
 
     /* get decoding parameters from header info */
     s->bit_alloc_params.sr_code     = hdr.sr_code;
+    s->bitstream_id                 = hdr.bitstream_id;
+    s->bitstream_mode               = hdr.bitstream_mode;
     s->channel_mode                 = hdr.channel_mode;
-    s->channel_layout               = hdr.channel_layout;
     s->lfe_on                       = hdr.lfe_on;
     s->bit_alloc_params.sr_shift    = hdr.sr_shift;
     s->sample_rate                  = hdr.sample_rate;
@@ -289,20 +287,27 @@ static int parse_frame_header(AC3DecodeContext *s)
     s->fbw_channels                 = s->channels - s->lfe_on;
     s->lfe_ch                       = s->fbw_channels + 1;
     s->frame_size                   = hdr.frame_size;
+    s->preferred_downmix            = AC3_DMIXMOD_NOTINDICATED;
     s->center_mix_level             = hdr.center_mix_level;
+    s->center_mix_level_ltrt        = 4; // -3.0dB
     s->surround_mix_level           = hdr.surround_mix_level;
+    s->surround_mix_level_ltrt      = 4; // -3.0dB
+    s->lfe_mix_level_exists         = 0;
     s->num_blocks                   = hdr.num_blocks;
     s->frame_type                   = hdr.frame_type;
     s->substreamid                  = hdr.substreamid;
+    s->dolby_surround_mode          = hdr.dolby_surround_mode;
+    s->dolby_surround_ex_mode       = AC3_DSUREXMOD_NOTINDICATED;
+    s->dolby_headphone_mode         = AC3_DHEADPHONMOD_NOTINDICATED;
 
-    if(s->lfe_on) {
-        s->start_freq[s->lfe_ch] = 0;
-        s->end_freq[s->lfe_ch] = 7;
+    if (s->lfe_on) {
+        s->start_freq[s->lfe_ch]     = 0;
+        s->end_freq[s->lfe_ch]       = 7;
         s->num_exp_groups[s->lfe_ch] = 2;
         s->channel_in_cpl[s->lfe_ch] = 0;
     }
 
-    if (hdr.bitstream_id <= 10) {
+    if (s->bitstream_id <= 10) {
         s->eac3                  = 0;
         s->snr_offset_strategy   = 2;
         s->block_switch_syntax   = 1;
@@ -319,7 +324,7 @@ static int parse_frame_header(AC3DecodeContext *s)
         return ff_eac3_parse_header(s);
     } else {
         av_log(s->avctx, AV_LOG_ERROR, "E-AC-3 support not compiled in\n");
-        return -1;
+        return AVERROR(ENOSYS);
     }
 }
 
@@ -330,42 +335,43 @@ static int parse_frame_header(AC3DecodeContext *s)
 static void set_downmix_coeffs(AC3DecodeContext *s)
 {
     int i;
-    float cmix = gain_levels[center_levels[s->center_mix_level]];
-    float smix = gain_levels[surround_levels[s->surround_mix_level]];
+    float cmix = gain_levels[s->  center_mix_level];
+    float smix = gain_levels[s->surround_mix_level];
     float norm0, norm1;
 
-    for(i=0; i<s->fbw_channels; i++) {
+    for (i = 0; i < s->fbw_channels; i++) {
         s->downmix_coeffs[i][0] = gain_levels[ac3_default_coeffs[s->channel_mode][i][0]];
         s->downmix_coeffs[i][1] = gain_levels[ac3_default_coeffs[s->channel_mode][i][1]];
     }
-    if(s->channel_mode > 1 && s->channel_mode & 1) {
+    if (s->channel_mode > 1 && s->channel_mode & 1) {
         s->downmix_coeffs[1][0] = s->downmix_coeffs[1][1] = cmix;
     }
-    if(s->channel_mode == AC3_CHMODE_2F1R || s->channel_mode == AC3_CHMODE_3F1R) {
+    if (s->channel_mode == AC3_CHMODE_2F1R || s->channel_mode == AC3_CHMODE_3F1R) {
         int nf = s->channel_mode - 2;
         s->downmix_coeffs[nf][0] = s->downmix_coeffs[nf][1] = smix * LEVEL_MINUS_3DB;
     }
-    if(s->channel_mode == AC3_CHMODE_2F2R || s->channel_mode == AC3_CHMODE_3F2R) {
+    if (s->channel_mode == AC3_CHMODE_2F2R || s->channel_mode == AC3_CHMODE_3F2R) {
         int nf = s->channel_mode - 4;
         s->downmix_coeffs[nf][0] = s->downmix_coeffs[nf+1][1] = smix;
     }
 
     /* renormalize */
     norm0 = norm1 = 0.0;
-    for(i=0; i<s->fbw_channels; i++) {
+    for (i = 0; i < s->fbw_channels; i++) {
         norm0 += s->downmix_coeffs[i][0];
         norm1 += s->downmix_coeffs[i][1];
     }
     norm0 = 1.0f / norm0;
     norm1 = 1.0f / norm1;
-    for(i=0; i<s->fbw_channels; i++) {
+    for (i = 0; i < s->fbw_channels; i++) {
         s->downmix_coeffs[i][0] *= norm0;
         s->downmix_coeffs[i][1] *= norm1;
     }
 
-    if(s->output_mode == AC3_CHMODE_MONO) {
-        for(i=0; i<s->fbw_channels; i++)
-            s->downmix_coeffs[i][0] = (s->downmix_coeffs[i][0] + s->downmix_coeffs[i][1]) * LEVEL_MINUS_3DB;
+    if (s->output_mode == AC3_CHMODE_MONO) {
+        for (i = 0; i < s->fbw_channels; i++)
+            s->downmix_coeffs[i][0] = (s->downmix_coeffs[i][0] +
+                                       s->downmix_coeffs[i][1]) * LEVEL_MINUS_3DB;
     }
 }
 
@@ -382,7 +388,7 @@ static int decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps,
 
     /* unpack groups */
     group_size = exp_strategy + (exp_strategy == EXP_D45);
-    for(grp=0,i=0; grp<ngrps; grp++) {
+    for (grp = 0, i = 0; grp < ngrps; grp++) {
         expacc = get_bits(gbc, 7);
         dexp[i++] = ungroup_3_in_7_bits_tab[expacc][0];
         dexp[i++] = ungroup_3_in_7_bits_tab[expacc][1];
@@ -391,15 +397,15 @@ static int decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps,
 
     /* convert to absolute exps and expand groups */
     prevexp = absexp;
-    for(i=0,j=0; i<ngrps*3; i++) {
+    for (i = 0, j = 0; i < ngrps * 3; i++) {
         prevexp += dexp[i] - 2;
         if (prevexp > 24U)
             return -1;
         switch (group_size) {
-            case 4: dexps[j++] = prevexp;
-                    dexps[j++] = prevexp;
-            case 2: dexps[j++] = prevexp;
-            case 1: dexps[j++] = prevexp;
+        case 4: dexps[j++] = prevexp;
+                dexps[j++] = prevexp;
+        case 2: dexps[j++] = prevexp;
+        case 1: dexps[j++] = prevexp;
         }
     }
     return 0;
@@ -422,7 +428,8 @@ static void calc_transform_coeffs_cpl(AC3DecodeContext *s)
             if (s->channel_in_cpl[ch]) {
                 int cpl_coord = s->cpl_coords[ch][band] << 5;
                 for (bin = band_start; bin < band_end; bin++) {
-                    s->fixed_coeffs[ch][bin] = MULH(s->fixed_coeffs[CPL_CH][bin] << 4, cpl_coord);
+                    s->fixed_coeffs[ch][bin] =
+                        MULH(s->fixed_coeffs[CPL_CH][bin] << 4, cpl_coord);
                 }
                 if (ch == 2 && s->phase_flags[band]) {
                     for (bin = band_start; bin < band_end; bin++)
@@ -437,7 +444,7 @@ static void calc_transform_coeffs_cpl(AC3DecodeContext *s)
 /**
  * Grouped mantissas for 3-level 5-level and 11-level quantization
  */
-typedef struct {
+typedef struct mant_groups {
     int b1_mant[2];
     int b2_mant[2];
     int b4_mant;
@@ -453,73 +460,71 @@ typedef struct {
 static void ac3_decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m)
 {
     int start_freq = s->start_freq[ch_index];
-    int end_freq = s->end_freq[ch_index];
-    uint8_t *baps = s->bap[ch_index];
-    int8_t *exps = s->dexps[ch_index];
-    int *coeffs = s->fixed_coeffs[ch_index];
-    int dither = (ch_index == CPL_CH) || s->dither_flag[ch_index];
+    int end_freq   = s->end_freq[ch_index];
+    uint8_t *baps  = s->bap[ch_index];
+    int8_t *exps   = s->dexps[ch_index];
+    int32_t *coeffs = s->fixed_coeffs[ch_index];
+    int dither     = (ch_index == CPL_CH) || s->dither_flag[ch_index];
     GetBitContext *gbc = &s->gbc;
     int freq;
 
-    for(freq = start_freq; freq < end_freq; freq++){
+    for (freq = start_freq; freq < end_freq; freq++) {
         int bap = baps[freq];
         int mantissa;
-        switch(bap){
-            case 0:
-                if (dither)
-                    mantissa = (av_lfg_get(&s->dith_state) & 0x7FFFFF) - 0x400000;
-                else
-                    mantissa = 0;
-                break;
-            case 1:
-                if(m->b1){
-                    m->b1--;
-                    mantissa = m->b1_mant[m->b1];
-                }
-                else{
-                    int bits      = get_bits(gbc, 5);
-                    mantissa      = b1_mantissas[bits][0];
-                    m->b1_mant[1] = b1_mantissas[bits][1];
-                    m->b1_mant[0] = b1_mantissas[bits][2];
-                    m->b1         = 2;
-                }
-                break;
-            case 2:
-                if(m->b2){
-                    m->b2--;
-                    mantissa = m->b2_mant[m->b2];
-                }
-                else{
-                    int bits      = get_bits(gbc, 7);
-                    mantissa      = b2_mantissas[bits][0];
-                    m->b2_mant[1] = b2_mantissas[bits][1];
-                    m->b2_mant[0] = b2_mantissas[bits][2];
-                    m->b2         = 2;
-                }
-                break;
-            case 3:
-                mantissa = b3_mantissas[get_bits(gbc, 3)];
-                break;
-            case 4:
-                if(m->b4){
-                    m->b4 = 0;
-                    mantissa = m->b4_mant;
-                }
-                else{
-                    int bits   = get_bits(gbc, 7);
-                    mantissa   = b4_mantissas[bits][0];
-                    m->b4_mant = b4_mantissas[bits][1];
-                    m->b4      = 1;
-                }
-                break;
-            case 5:
-                mantissa = b5_mantissas[get_bits(gbc, 4)];
-                break;
-            default: /* 6 to 15 */
-                mantissa = get_bits(gbc, quantization_tab[bap]);
-                /* Shift mantissa and sign-extend it. */
-                mantissa = (mantissa << (32-quantization_tab[bap]))>>8;
-                break;
+        switch (bap) {
+        case 0:
+            /* random noise with approximate range of -0.707 to 0.707 */
+            if (dither)
+                mantissa = (av_lfg_get(&s->dith_state) / 362) - 5932275;
+            else
+                mantissa = 0;
+            break;
+        case 1:
+            if (m->b1) {
+                m->b1--;
+                mantissa = m->b1_mant[m->b1];
+            } else {
+                int bits      = get_bits(gbc, 5);
+                mantissa      = b1_mantissas[bits][0];
+                m->b1_mant[1] = b1_mantissas[bits][1];
+                m->b1_mant[0] = b1_mantissas[bits][2];
+                m->b1         = 2;
+            }
+            break;
+        case 2:
+            if (m->b2) {
+                m->b2--;
+                mantissa = m->b2_mant[m->b2];
+            } else {
+                int bits      = get_bits(gbc, 7);
+                mantissa      = b2_mantissas[bits][0];
+                m->b2_mant[1] = b2_mantissas[bits][1];
+                m->b2_mant[0] = b2_mantissas[bits][2];
+                m->b2         = 2;
+            }
+            break;
+        case 3:
+            mantissa = b3_mantissas[get_bits(gbc, 3)];
+            break;
+        case 4:
+            if (m->b4) {
+                m->b4 = 0;
+                mantissa = m->b4_mant;
+            } else {
+                int bits   = get_bits(gbc, 7);
+                mantissa   = b4_mantissas[bits][0];
+                m->b4_mant = b4_mantissas[bits][1];
+                m->b4      = 1;
+            }
+            break;
+        case 5:
+            mantissa = b5_mantissas[get_bits(gbc, 4)];
+            break;
+        default: /* 6 to 15 */
+            /* Shift mantissa and sign-extend it. */
+            mantissa = get_sbits(gbc, quantization_tab[bap]);
+            mantissa <<= 24 - quantization_tab[bap];
+            break;
         }
         coeffs[freq] = mantissa >> exps[freq];
     }
@@ -533,18 +538,18 @@ static void ac3_decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, ma
 static void remove_dithering(AC3DecodeContext *s) {
     int ch, i;
 
-    for(ch=1; ch<=s->fbw_channels; ch++) {
-        if(!s->dither_flag[ch] && s->channel_in_cpl[ch]) {
-            for(i = s->start_freq[CPL_CH]; i<s->end_freq[CPL_CH]; i++) {
-                if(!s->bap[CPL_CH][i])
+    for (ch = 1; ch <= s->fbw_channels; ch++) {
+        if (!s->dither_flag[ch] && s->channel_in_cpl[ch]) {
+            for (i = s->start_freq[CPL_CH]; i < s->end_freq[CPL_CH]; i++) {
+                if (!s->bap[CPL_CH][i])
                     s->fixed_coeffs[ch][i] = 0;
             }
         }
     }
 }
 
-static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch,
-                                    mant_groups *m)
+static inline void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk,
+                                              int ch, mant_groups *m)
 {
     if (!s->channel_uses_aht[ch]) {
         ac3_decode_transform_coeffs_ch(s, ch, m);
@@ -563,7 +568,7 @@ static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch,
 /**
  * Decode the transform coefficients.
  */
-static void decode_transform_coeffs(AC3DecodeContext *s, int blk)
+static inline void decode_transform_coeffs(AC3DecodeContext *s, int blk)
 {
     int ch, end;
     int got_cplchan = 0;
@@ -574,7 +579,7 @@ static void decode_transform_coeffs(AC3DecodeContext *s, int blk)
     for (ch = 1; ch <= s->channels; ch++) {
         /* transform coefficients for full-bandwidth channel */
         decode_transform_coeffs_ch(s, blk, ch, &m);
-        /* tranform coefficients for coupling channel come right after the
+        /* transform coefficients for coupling channel come right after the
            coefficients for the first coupled channel*/
         if (s->channel_in_cpl[ch])  {
             if (!got_cplchan) {
@@ -588,7 +593,7 @@ static void decode_transform_coeffs(AC3DecodeContext *s, int blk)
         }
         do
             s->fixed_coeffs[ch][end] = 0;
-        while(++end < 256);
+        while (++end < 256);
     }
 
     /* zero the dithered coefficients for appropriate channels */
@@ -606,10 +611,10 @@ static void do_rematrixing(AC3DecodeContext *s)
 
     end = FFMIN(s->end_freq[1], s->end_freq[2]);
 
-    for(bnd=0; bnd<s->num_rematrixing_bands; bnd++) {
-        if(s->rematrixing_flags[bnd]) {
-            bndend = FFMIN(end, ff_ac3_rematrix_band_tab[bnd+1]);
-            for(i=ff_ac3_rematrix_band_tab[bnd]; i<bndend; i++) {
+    for (bnd = 0; bnd < s->num_rematrixing_bands; bnd++) {
+        if (s->rematrixing_flags[bnd]) {
+            bndend = FFMIN(end, ff_ac3_rematrix_band_tab[bnd + 1]);
+            for (i = ff_ac3_rematrix_band_tab[bnd]; i < bndend; i++) {
                 int tmp0 = s->fixed_coeffs[1][i];
                 s->fixed_coeffs[1][i] += s->fixed_coeffs[2][i];
                 s->fixed_coeffs[2][i]  = tmp0 - s->fixed_coeffs[2][i];
@@ -626,52 +631,24 @@ static void do_rematrixing(AC3DecodeContext *s)
 static inline void do_imdct(AC3DecodeContext *s, int channels)
 {
     int ch;
-    float add_bias = s->add_bias;
-    if(s->out_channels==1 && channels>1)
-        add_bias *= LEVEL_MINUS_3DB; // compensate for the gain in downmix
 
-    for (ch=1; ch<=channels; ch++) {
+    for (ch = 1; ch <= channels; ch++) {
         if (s->block_switch[ch]) {
             int i;
-            float *x = s->tmp_output+128;
-            for(i=0; i<128; i++)
-                x[i] = s->transform_coeffs[ch][2*i];
-            ff_imdct_half(&s->imdct_256, s->tmp_output, x);
-            s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, add_bias, 128);
-            for(i=0; i<128; i++)
-                x[i] = s->transform_coeffs[ch][2*i+1];
-            ff_imdct_half(&s->imdct_256, s->delay[ch-1], x);
+            float *x = s->tmp_output + 128;
+            for (i = 0; i < 128; i++)
+                x[i] = s->transform_coeffs[ch][2 * i];
+            s->imdct_256.imdct_half(&s->imdct_256, s->tmp_output, x);
+            s->fdsp.vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1],
+                                       s->tmp_output, s->window, 128);
+            for (i = 0; i < 128; i++)
+                x[i] = s->transform_coeffs[ch][2 * i + 1];
+            s->imdct_256.imdct_half(&s->imdct_256, s->delay[ch - 1], x);
         } else {
-            ff_imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]);
-            s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, add_bias, 128);
-            memcpy(s->delay[ch-1], s->tmp_output+128, 128*sizeof(float));
-        }
-    }
-}
-
-/**
- * Downmix the output to mono or stereo.
- */
-void ff_ac3_downmix_c(float (*samples)[256], float (*matrix)[2], int out_ch, int in_ch, int len)
-{
-    int i, j;
-    float v0, v1;
-    if(out_ch == 2) {
-        for(i=0; i<len; i++) {
-            v0 = v1 = 0.0f;
-            for(j=0; j<in_ch; j++) {
-                v0 += samples[j][i] * matrix[j][0];
-                v1 += samples[j][i] * matrix[j][1];
-            }
-            samples[0][i] = v0;
-            samples[1][i] = v1;
-        }
-    } else if(out_ch == 1) {
-        for(i=0; i<len; i++) {
-            v0 = 0.0f;
-            for(j=0; j<in_ch; j++)
-                v0 += samples[j][i] * matrix[j][0];
-            samples[0][i] = v0;
+            s->imdct_512.imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]);
+            s->fdsp.vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1],
+                                       s->tmp_output, s->window, 128);
+            memcpy(s->delay[ch - 1], s->tmp_output + 128, 128 * sizeof(float));
         }
     }
 }
@@ -682,25 +659,25 @@ void ff_ac3_downmix_c(float (*samples)[256], float (*matrix)[2], int out_ch, int
 static void ac3_upmix_delay(AC3DecodeContext *s)
 {
     int channel_data_size = sizeof(s->delay[0]);
-    switch(s->channel_mode) {
-        case AC3_CHMODE_DUALMONO:
-        case AC3_CHMODE_STEREO:
-            /* upmix mono to stereo */
-            memcpy(s->delay[1], s->delay[0], channel_data_size);
-            break;
-        case AC3_CHMODE_2F2R:
-            memset(s->delay[3], 0, channel_data_size);
-        case AC3_CHMODE_2F1R:
-            memset(s->delay[2], 0, channel_data_size);
-            break;
-        case AC3_CHMODE_3F2R:
-            memset(s->delay[4], 0, channel_data_size);
-        case AC3_CHMODE_3F1R:
-            memset(s->delay[3], 0, channel_data_size);
-        case AC3_CHMODE_3F:
-            memcpy(s->delay[2], s->delay[1], channel_data_size);
-            memset(s->delay[1], 0, channel_data_size);
-            break;
+    switch (s->channel_mode) {
+    case AC3_CHMODE_DUALMONO:
+    case AC3_CHMODE_STEREO:
+        /* upmix mono to stereo */
+        memcpy(s->delay[1], s->delay[0], channel_data_size);
+        break;
+    case AC3_CHMODE_2F2R:
+        memset(s->delay[3], 0, channel_data_size);
+    case AC3_CHMODE_2F1R:
+        memset(s->delay[2], 0, channel_data_size);
+        break;
+    case AC3_CHMODE_3F2R:
+        memset(s->delay[4], 0, channel_data_size);
+    case AC3_CHMODE_3F1R:
+        memset(s->delay[3], 0, channel_data_size);
+    case AC3_CHMODE_3F:
+        memcpy(s->delay[2], s->delay[1], channel_data_size);
+        memset(s->delay[1], 0, channel_data_size);
+        break;
     }
 }
 
@@ -753,7 +730,7 @@ static void decode_band_structure(GetBitContext *gbc, int blk, int eac3,
         bnd_sz[0] = ecpl ? 6 : 12;
         for (bnd = 0, subbnd = 1; subbnd < n_subbands; subbnd++) {
             int subbnd_size = (ecpl && subbnd < 4) ? 6 : 12;
-            if (band_struct[subbnd-1]) {
+            if (band_struct[subbnd - 1]) {
                 n_bands--;
                 bnd_sz[bnd] += subbnd_size;
             } else {
@@ -769,6 +746,221 @@ static void decode_band_structure(GetBitContext *gbc, int blk, int eac3,
         memcpy(band_sizes, bnd_sz, n_bands);
 }
 
+static inline int spx_strategy(AC3DecodeContext *s, int blk)
+{
+    GetBitContext *bc = &s->gbc;
+    int fbw_channels = s->fbw_channels;
+    int dst_start_freq, dst_end_freq, src_start_freq,
+        start_subband, end_subband, ch;
+
+    /* determine which channels use spx */
+    if (s->channel_mode == AC3_CHMODE_MONO) {
+        s->channel_uses_spx[1] = 1;
+    } else {
+        for (ch = 1; ch <= fbw_channels; ch++)
+            s->channel_uses_spx[ch] = get_bits1(bc);
+    }
+
+    /* get the frequency bins of the spx copy region and the spx start
+       and end subbands */
+    dst_start_freq = get_bits(bc, 2);
+    start_subband  = get_bits(bc, 3) + 2;
+    if (start_subband > 7)
+        start_subband += start_subband - 7;
+    end_subband    = get_bits(bc, 3) + 5;
+    if (end_subband   > 7)
+        end_subband   += end_subband   - 7;
+    dst_start_freq = dst_start_freq * 12 + 25;
+    src_start_freq = start_subband  * 12 + 25;
+    dst_end_freq   = end_subband    * 12 + 25;
+
+    /* check validity of spx ranges */
+    if (start_subband >= end_subband) {
+        av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension "
+               "range (%d >= %d)\n", start_subband, end_subband);
+        return AVERROR_INVALIDDATA;
+    }
+    if (dst_start_freq >= src_start_freq) {
+        av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension "
+               "copy start bin (%d >= %d)\n", dst_start_freq, src_start_freq);
+        return AVERROR_INVALIDDATA;
+    }
+
+    s->spx_dst_start_freq = dst_start_freq;
+    s->spx_src_start_freq = src_start_freq;
+    s->spx_dst_end_freq   = dst_end_freq;
+
+    decode_band_structure(bc, blk, s->eac3, 0,
+                          start_subband, end_subband,
+                          ff_eac3_default_spx_band_struct,
+                          &s->num_spx_bands,
+                          s->spx_band_sizes);
+
+    return 0;
+}
+
+static inline void spx_coordinates(AC3DecodeContext *s)
+{
+    GetBitContext *bc = &s->gbc;
+    int fbw_channels = s->fbw_channels;
+    int ch, bnd;
+
+    for (ch = 1; ch <= fbw_channels; ch++) {
+        if (s->channel_uses_spx[ch]) {
+            if (s->first_spx_coords[ch] || get_bits1(bc)) {
+                float spx_blend;
+                int bin, master_spx_coord;
+
+                s->first_spx_coords[ch] = 0;
+                spx_blend        = get_bits(bc, 5) * (1.0f / 32);
+                master_spx_coord = get_bits(bc, 2) * 3;
+
+                bin = s->spx_src_start_freq;
+                for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
+                    int bandsize;
+                    int spx_coord_exp, spx_coord_mant;
+                    float nratio, sblend, nblend, spx_coord;
+
+                    /* calculate blending factors */
+                    bandsize = s->spx_band_sizes[bnd];
+                    nratio = ((float)((bin + (bandsize >> 1))) / s->spx_dst_end_freq) - spx_blend;
+                    nratio = av_clipf(nratio, 0.0f, 1.0f);
+                    nblend = sqrtf(3.0f * nratio); // noise is scaled by sqrt(3)
+                                                   // to give unity variance
+                    sblend = sqrtf(1.0f - nratio);
+                    bin += bandsize;
+
+                    /* decode spx coordinates */
+                    spx_coord_exp  = get_bits(bc, 4);
+                    spx_coord_mant = get_bits(bc, 2);
+                    if (spx_coord_exp == 15) spx_coord_mant <<= 1;
+                    else                     spx_coord_mant += 4;
+                    spx_coord_mant <<= (25 - spx_coord_exp - master_spx_coord);
+                    spx_coord = spx_coord_mant * (1.0f / (1 << 23));
+
+                    /* multiply noise and signal blending factors by spx coordinate */
+                    s->spx_noise_blend [ch][bnd] = nblend * spx_coord;
+                    s->spx_signal_blend[ch][bnd] = sblend * spx_coord;
+                }
+            }
+        } else {
+            s->first_spx_coords[ch] = 1;
+        }
+    }
+}
+
+static inline int coupling_strategy(AC3DecodeContext *s, int blk,
+                                    uint8_t *bit_alloc_stages)
+{
+    GetBitContext *bc = &s->gbc;
+    int fbw_channels = s->fbw_channels;
+    int channel_mode = s->channel_mode;
+    int ch;
+
+    memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
+    if (!s->eac3)
+        s->cpl_in_use[blk] = get_bits1(bc);
+    if (s->cpl_in_use[blk]) {
+        /* coupling in use */
+        int cpl_start_subband, cpl_end_subband;
+
+        if (channel_mode < AC3_CHMODE_STEREO) {
+            av_log(s->avctx, AV_LOG_ERROR, "coupling not allowed in mono or dual-mono\n");
+            return AVERROR_INVALIDDATA;
+        }
+
+        /* check for enhanced coupling */
+        if (s->eac3 && get_bits1(bc)) {
+            /* TODO: parse enhanced coupling strategy info */
+            avpriv_request_sample(s->avctx, "Enhanced coupling");
+            return AVERROR_PATCHWELCOME;
+        }
+
+        /* determine which channels are coupled */
+        if (s->eac3 && s->channel_mode == AC3_CHMODE_STEREO) {
+            s->channel_in_cpl[1] = 1;
+            s->channel_in_cpl[2] = 1;
+        } else {
+            for (ch = 1; ch <= fbw_channels; ch++)
+                s->channel_in_cpl[ch] = get_bits1(bc);
+        }
+
+        /* phase flags in use */
+        if (channel_mode == AC3_CHMODE_STEREO)
+            s->phase_flags_in_use = get_bits1(bc);
+
+        /* coupling frequency range */
+        cpl_start_subband = get_bits(bc, 4);
+        cpl_end_subband = s->spx_in_use ? (s->spx_src_start_freq - 37) / 12 :
+                                          get_bits(bc, 4) + 3;
+        if (cpl_start_subband >= cpl_end_subband) {
+            av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n",
+                   cpl_start_subband, cpl_end_subband);
+            return AVERROR_INVALIDDATA;
+        }
+        s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37;
+        s->end_freq[CPL_CH]   = cpl_end_subband   * 12 + 37;
+
+        decode_band_structure(bc, blk, s->eac3, 0, cpl_start_subband,
+                              cpl_end_subband,
+                              ff_eac3_default_cpl_band_struct,
+                              &s->num_cpl_bands, s->cpl_band_sizes);
+    } else {
+        /* coupling not in use */
+        for (ch = 1; ch <= fbw_channels; ch++) {
+            s->channel_in_cpl[ch] = 0;
+            s->first_cpl_coords[ch] = 1;
+        }
+        s->first_cpl_leak = s->eac3;
+        s->phase_flags_in_use = 0;
+    }
+
+    return 0;
+}
+
+static inline int coupling_coordinates(AC3DecodeContext *s, int blk)
+{
+    GetBitContext *bc = &s->gbc;
+    int fbw_channels = s->fbw_channels;
+    int ch, bnd;
+    int cpl_coords_exist = 0;
+
+    for (ch = 1; ch <= fbw_channels; ch++) {
+        if (s->channel_in_cpl[ch]) {
+            if ((s->eac3 && s->first_cpl_coords[ch]) || get_bits1(bc)) {
+                int master_cpl_coord, cpl_coord_exp, cpl_coord_mant;
+                s->first_cpl_coords[ch] = 0;
+                cpl_coords_exist = 1;
+                master_cpl_coord = 3 * get_bits(bc, 2);
+                for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
+                    cpl_coord_exp  = get_bits(bc, 4);
+                    cpl_coord_mant = get_bits(bc, 4);
+                    if (cpl_coord_exp == 15)
+                        s->cpl_coords[ch][bnd] = cpl_coord_mant << 22;
+                    else
+                        s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16) << 21;
+                    s->cpl_coords[ch][bnd] >>= (cpl_coord_exp + master_cpl_coord);
+                }
+            } else if (!blk) {
+                av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must "
+                       "be present in block 0\n");
+                return AVERROR_INVALIDDATA;
+            }
+        } else {
+            /* channel not in coupling */
+            s->first_cpl_coords[ch] = 1;
+        }
+    }
+    /* phase flags */
+    if (s->channel_mode == AC3_CHMODE_STEREO && cpl_coords_exist) {
+        for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
+            s->phase_flags[bnd] = s->phase_flags_in_use ? get_bits1(bc) : 0;
+        }
+    }
+
+    return 0;
+}
+
 /**
  * Decode a single audio block from the AC-3 bitstream.
  */
@@ -776,21 +968,19 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
 {
     int fbw_channels = s->fbw_channels;
     int channel_mode = s->channel_mode;
-    int i, bnd, seg, ch;
+    int i, bnd, seg, ch, ret;
     int different_transforms;
     int downmix_output;
     int cpl_in_use;
     GetBitContext *gbc = &s->gbc;
-    uint8_t bit_alloc_stages[AC3_MAX_CHANNELS];
-
-    memset(bit_alloc_stages, 0, AC3_MAX_CHANNELS);
+    uint8_t bit_alloc_stages[AC3_MAX_CHANNELS] = { 0 };
 
     /* block switch flags */
     different_transforms = 0;
     if (s->block_switch_syntax) {
         for (ch = 1; ch <= fbw_channels; ch++) {
             s->block_switch[ch] = get_bits1(gbc);
-            if(ch > 1 && s->block_switch[ch] != s->block_switch[1])
+            if (ch > 1 && s->block_switch[ch] != s->block_switch[1])
                 different_transforms = 1;
         }
     }
@@ -803,65 +993,27 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     }
 
     /* dynamic range */
-    i = !(s->channel_mode);
+    i = !s->channel_mode;
     do {
-        if(get_bits1(gbc)) {
-            s->dynamic_range[i] = ((dynamic_range_tab[get_bits(gbc, 8)]-1.0) *
-                                  s->avctx->drc_scale)+1.0;
-        } else if(blk == 0) {
+        if (get_bits1(gbc)) {
+            /* Allow asymmetric application of DRC when drc_scale > 1.
+               Amplification of quiet sounds is enhanced */
+            float range = dynamic_range_tab[get_bits(gbc, 8)];
+            if (range > 1.0 || s->drc_scale <= 1.0)
+                s->dynamic_range[i] = powf(range, s->drc_scale);
+            else
+                s->dynamic_range[i] = range;
+        } else if (blk == 0) {
             s->dynamic_range[i] = 1.0f;
         }
-    } while(i--);
+    } while (i--);
 
     /* spectral extension strategy */
     if (s->eac3 && (!blk || get_bits1(gbc))) {
         s->spx_in_use = get_bits1(gbc);
         if (s->spx_in_use) {
-            int dst_start_freq, dst_end_freq, src_start_freq,
-                start_subband, end_subband;
-
-            /* determine which channels use spx */
-            if (s->channel_mode == AC3_CHMODE_MONO) {
-                s->channel_uses_spx[1] = 1;
-            } else {
-                for (ch = 1; ch <= fbw_channels; ch++)
-                    s->channel_uses_spx[ch] = get_bits1(gbc);
-            }
-
-            /* get the frequency bins of the spx copy region and the spx start
-               and end subbands */
-            dst_start_freq = get_bits(gbc, 2);
-            start_subband  = get_bits(gbc, 3) + 2;
-            if (start_subband > 7)
-                start_subband += start_subband - 7;
-            end_subband    = get_bits(gbc, 3) + 5;
-            if (end_subband   > 7)
-                end_subband   += end_subband   - 7;
-            dst_start_freq = dst_start_freq * 12 + 25;
-            src_start_freq = start_subband  * 12 + 25;
-            dst_end_freq   = end_subband    * 12 + 25;
-
-            /* check validity of spx ranges */
-            if (start_subband >= end_subband) {
-                av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension "
-                       "range (%d >= %d)\n", start_subband, end_subband);
-                return -1;
-            }
-            if (dst_start_freq >= src_start_freq) {
-                av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension "
-                       "copy start bin (%d >= %d)\n", dst_start_freq, src_start_freq);
-                return -1;
-            }
-
-            s->spx_dst_start_freq = dst_start_freq;
-            s->spx_src_start_freq = src_start_freq;
-            s->spx_dst_end_freq   = dst_end_freq;
-
-            decode_band_structure(gbc, blk, s->eac3, 0,
-                                  start_subband, end_subband,
-                                  ff_eac3_default_spx_band_struct,
-                                  &s->num_spx_bands,
-                                  s->spx_band_sizes);
+            if ((ret = spx_strategy(s, blk)) < 0)
+                return ret;
         } else {
             for (ch = 1; ch <= fbw_channels; ch++) {
                 s->channel_uses_spx[ch] = 0;
@@ -871,113 +1023,18 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     }
 
     /* spectral extension coordinates */
-    if (s->spx_in_use) {
-        for (ch = 1; ch <= fbw_channels; ch++) {
-            if (s->channel_uses_spx[ch]) {
-                if (s->first_spx_coords[ch] || get_bits1(gbc)) {
-                    float spx_blend;
-                    int bin, master_spx_coord;
-
-                    s->first_spx_coords[ch] = 0;
-                    spx_blend = get_bits(gbc, 5) * (1.0f/32);
-                    master_spx_coord = get_bits(gbc, 2) * 3;
-
-                    bin = s->spx_src_start_freq;
-                    for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
-                        int bandsize;
-                        int spx_coord_exp, spx_coord_mant;
-                        float nratio, sblend, nblend, spx_coord;
-
-                        /* calculate blending factors */
-                        bandsize = s->spx_band_sizes[bnd];
-                        nratio = ((float)((bin + (bandsize >> 1))) / s->spx_dst_end_freq) - spx_blend;
-                        nratio = av_clipf(nratio, 0.0f, 1.0f);
-                        nblend = sqrtf(3.0f * nratio); // noise is scaled by sqrt(3) to give unity variance
-                        sblend = sqrtf(1.0f - nratio);
-                        bin += bandsize;
-
-                        /* decode spx coordinates */
-                        spx_coord_exp  = get_bits(gbc, 4);
-                        spx_coord_mant = get_bits(gbc, 2);
-                        if (spx_coord_exp == 15) spx_coord_mant <<= 1;
-                        else                     spx_coord_mant += 4;
-                        spx_coord_mant <<= (25 - spx_coord_exp - master_spx_coord);
-                        spx_coord = spx_coord_mant * (1.0f/(1<<23));
-
-                        /* multiply noise and signal blending factors by spx coordinate */
-                        s->spx_noise_blend [ch][bnd] = nblend * spx_coord;
-                        s->spx_signal_blend[ch][bnd] = sblend * spx_coord;
-                    }
-                }
-            } else {
-                s->first_spx_coords[ch] = 1;
-            }
-        }
-    }
+    if (s->spx_in_use)
+        spx_coordinates(s);
 
     /* coupling strategy */
     if (s->eac3 ? s->cpl_strategy_exists[blk] : get_bits1(gbc)) {
-        memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
-        if (!s->eac3)
-            s->cpl_in_use[blk] = get_bits1(gbc);
-        if (s->cpl_in_use[blk]) {
-            /* coupling in use */
-            int cpl_start_subband, cpl_end_subband;
-
-            if (channel_mode < AC3_CHMODE_STEREO) {
-                av_log(s->avctx, AV_LOG_ERROR, "coupling not allowed in mono or dual-mono\n");
-                return -1;
-            }
-
-            /* check for enhanced coupling */
-            if (s->eac3 && get_bits1(gbc)) {
-                /* TODO: parse enhanced coupling strategy info */
-                av_log_missing_feature(s->avctx, "Enhanced coupling", 1);
-                return -1;
-            }
-
-            /* determine which channels are coupled */
-            if (s->eac3 && s->channel_mode == AC3_CHMODE_STEREO) {
-                s->channel_in_cpl[1] = 1;
-                s->channel_in_cpl[2] = 1;
-            } else {
-                for (ch = 1; ch <= fbw_channels; ch++)
-                    s->channel_in_cpl[ch] = get_bits1(gbc);
-            }
-
-            /* phase flags in use */
-            if (channel_mode == AC3_CHMODE_STEREO)
-                s->phase_flags_in_use = get_bits1(gbc);
-
-            /* coupling frequency range */
-            cpl_start_subband = get_bits(gbc, 4);
-            cpl_end_subband = s->spx_in_use ? (s->spx_src_start_freq - 37) / 12 :
-                                              get_bits(gbc, 4) + 3;
-            if (cpl_start_subband >= cpl_end_subband) {
-                av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n",
-                       cpl_start_subband, cpl_end_subband);
-                return -1;
-            }
-            s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37;
-            s->end_freq[CPL_CH]   = cpl_end_subband   * 12 + 37;
-
-            decode_band_structure(gbc, blk, s->eac3, 0, cpl_start_subband,
-                                  cpl_end_subband,
-                                  ff_eac3_default_cpl_band_struct,
-                                  &s->num_cpl_bands, s->cpl_band_sizes);
-        } else {
-            /* coupling not in use */
-            for (ch = 1; ch <= fbw_channels; ch++) {
-                s->channel_in_cpl[ch] = 0;
-                s->first_cpl_coords[ch] = 1;
-            }
-            s->first_cpl_leak = s->eac3;
-            s->phase_flags_in_use = 0;
-        }
+        if ((ret = coupling_strategy(s, blk, bit_alloc_stages)) < 0)
+            return ret;
     } else if (!s->eac3) {
-        if(!blk) {
-            av_log(s->avctx, AV_LOG_ERROR, "new coupling strategy must be present in block 0\n");
-            return -1;
+        if (!blk) {
+            av_log(s->avctx, AV_LOG_ERROR, "new coupling strategy must "
+                   "be present in block 0\n");
+            return AVERROR_INVALIDDATA;
         } else {
             s->cpl_in_use[blk] = s->cpl_in_use[blk-1];
         }
@@ -986,39 +1043,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
 
     /* coupling coordinates */
     if (cpl_in_use) {
-        int cpl_coords_exist = 0;
-
-        for (ch = 1; ch <= fbw_channels; ch++) {
-            if (s->channel_in_cpl[ch]) {
-                if ((s->eac3 && s->first_cpl_coords[ch]) || get_bits1(gbc)) {
-                    int master_cpl_coord, cpl_coord_exp, cpl_coord_mant;
-                    s->first_cpl_coords[ch] = 0;
-                    cpl_coords_exist = 1;
-                    master_cpl_coord = 3 * get_bits(gbc, 2);
-                    for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
-                        cpl_coord_exp = get_bits(gbc, 4);
-                        cpl_coord_mant = get_bits(gbc, 4);
-                        if (cpl_coord_exp == 15)
-                            s->cpl_coords[ch][bnd] = cpl_coord_mant << 22;
-                        else
-                            s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16) << 21;
-                        s->cpl_coords[ch][bnd] >>= (cpl_coord_exp + master_cpl_coord);
-                    }
-                } else if (!blk) {
-                    av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must be present in block 0\n");
-                    return -1;
-                }
-            } else {
-                /* channel not in coupling */
-                s->first_cpl_coords[ch] = 1;
-            }
-        }
-        /* phase flags */
-        if (channel_mode == AC3_CHMODE_STEREO && cpl_coords_exist) {
-            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
-                s->phase_flags[bnd] = s->phase_flags_in_use? get_bits1(gbc) : 0;
-            }
-        }
+        if ((ret = coupling_coordinates(s, blk)) < 0)
+            return ret;
     }
 
     /* stereo rematrixing strategy and band structure */
@@ -1030,10 +1056,11 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             } else if (s->spx_in_use && s->spx_src_start_freq <= 61) {
                 s->num_rematrixing_bands--;
             }
-            for(bnd=0; bnd<s->num_rematrixing_bands; bnd++)
+            for (bnd = 0; bnd < s->num_rematrixing_bands; bnd++)
                 s->rematrixing_flags[bnd] = get_bits1(gbc);
         } else if (!blk) {
-            av_log(s->avctx, AV_LOG_WARNING, "Warning: new rematrixing strategy not present in block 0\n");
+            av_log(s->avctx, AV_LOG_WARNING, "Warning: "
+                   "new rematrixing strategy not present in block 0\n");
             s->num_rematrixing_bands = 0;
         }
     }
@@ -1042,7 +1069,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     for (ch = !cpl_in_use; ch <= s->channels; ch++) {
         if (!s->eac3)
             s->exp_strategy[blk][ch] = get_bits(gbc, 2 - (ch == s->lfe_ch));
-        if(s->exp_strategy[blk][ch] != EXP_REUSE)
+        if (s->exp_strategy[blk][ch] != EXP_REUSE)
             bit_alloc_stages[ch] = 3;
     }
 
@@ -1060,13 +1087,13 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
                 int bandwidth_code = get_bits(gbc, 6);
                 if (bandwidth_code > 60) {
                     av_log(s->avctx, AV_LOG_ERROR, "bandwidth code = %d > 60\n", bandwidth_code);
-                    return -1;
+                    return AVERROR_INVALIDDATA;
                 }
                 s->end_freq[ch] = bandwidth_code * 3 + 73;
             }
             group_size = 3 << (s->exp_strategy[blk][ch] - 1);
-            s->num_exp_groups[ch] = (s->end_freq[ch]+group_size-4) / group_size;
-            if(blk > 0 && s->end_freq[ch] != prev)
+            s->num_exp_groups[ch] = (s->end_freq[ch] + group_size-4) / group_size;
+            if (blk > 0 && s->end_freq[ch] != prev)
                 memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
         }
     }
@@ -1083,9 +1110,9 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
                                  s->num_exp_groups[ch], s->dexps[ch][0],
                                  &s->dexps[ch][s->start_freq[ch]+!!ch])) {
                 av_log(s->avctx, AV_LOG_ERROR, "exponent out-of-range\n");
-                return -1;
+                return AVERROR_INVALIDDATA;
             }
-            if(ch != CPL_CH && ch != s->lfe_ch)
+            if (ch != CPL_CH && ch != s->lfe_ch)
                 skip_bits(gbc, 2); /* skip gainrng */
         }
     }
@@ -1098,17 +1125,18 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             s->bit_alloc_params.slow_gain  = ff_ac3_slow_gain_tab[get_bits(gbc, 2)];
             s->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gbc, 2)];
             s->bit_alloc_params.floor  = ff_ac3_floor_tab[get_bits(gbc, 3)];
-            for(ch=!cpl_in_use; ch<=s->channels; ch++)
+            for (ch = !cpl_in_use; ch <= s->channels; ch++)
                 bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
         } else if (!blk) {
-            av_log(s->avctx, AV_LOG_ERROR, "new bit allocation info must be present in block 0\n");
-            return -1;
+            av_log(s->avctx, AV_LOG_ERROR, "new bit allocation info must "
+                   "be present in block 0\n");
+            return AVERROR_INVALIDDATA;
         }
     }
 
     /* signal-to-noise ratio offsets and fast gains (signal-to-mask ratios) */
-    if(!s->eac3 || !blk){
-        if(s->snr_offset_strategy && get_bits1(gbc)) {
+    if (!s->eac3 || !blk) {
+        if (s->snr_offset_strategy && get_bits1(gbc)) {
             int snr = 0;
             int csnr;
             csnr = (get_bits(gbc, 6) - 15) << 4;
@@ -1117,7 +1145,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
                 if (ch == i || s->snr_offset_strategy == 2)
                     snr = (csnr + get_bits(gbc, 4)) << 2;
                 /* run at least last bit allocation stage if snr offset changes */
-                if(blk && s->snr_offset[ch] != snr) {
+                if (blk && s->snr_offset[ch] != snr) {
                     bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 1);
                 }
                 s->snr_offset[ch] = snr;
@@ -1127,13 +1155,13 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
                     int prev = s->fast_gain[ch];
                     s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)];
                     /* run last 2 bit allocation stages if fast gain changes */
-                    if(blk && prev != s->fast_gain[ch])
+                    if (blk && prev != s->fast_gain[ch])
                         bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
                 }
             }
         } else if (!s->eac3 && !blk) {
             av_log(s->avctx, AV_LOG_ERROR, "new snr offsets must be present in block 0\n");
-            return -1;
+            return AVERROR_INVALIDDATA;
         }
     }
 
@@ -1143,7 +1171,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             int prev = s->fast_gain[ch];
             s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)];
             /* run last 2 bit allocation stages if fast gain changes */
-            if(blk && prev != s->fast_gain[ch])
+            if (blk && prev != s->fast_gain[ch])
                 bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
         }
     } else if (s->eac3 && !blk) {
@@ -1163,15 +1191,16 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             int sl = get_bits(gbc, 3);
             /* run last 2 bit allocation stages for coupling channel if
                coupling leak changes */
-            if(blk && (fl != s->bit_alloc_params.cpl_fast_leak ||
-                       sl != s->bit_alloc_params.cpl_slow_leak)) {
+            if (blk && (fl != s->bit_alloc_params.cpl_fast_leak ||
+                sl != s->bit_alloc_params.cpl_slow_leak)) {
                 bit_alloc_stages[CPL_CH] = FFMAX(bit_alloc_stages[CPL_CH], 2);
             }
             s->bit_alloc_params.cpl_fast_leak = fl;
             s->bit_alloc_params.cpl_slow_leak = sl;
         } else if (!s->eac3 && !blk) {
-            av_log(s->avctx, AV_LOG_ERROR, "new coupling leak info must be present in block 0\n");
-            return -1;
+            av_log(s->avctx, AV_LOG_ERROR, "new coupling leak info must "
+                   "be present in block 0\n");
+            return AVERROR_INVALIDDATA;
         }
         s->first_cpl_leak = 0;
     }
@@ -1183,55 +1212,55 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             s->dba_mode[ch] = get_bits(gbc, 2);
             if (s->dba_mode[ch] == DBA_RESERVED) {
                 av_log(s->avctx, AV_LOG_ERROR, "delta bit allocation strategy reserved\n");
-                return -1;
+                return AVERROR_INVALIDDATA;
             }
             bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
         }
         /* channel delta offset, len and bit allocation */
         for (ch = !cpl_in_use; ch <= fbw_channels; ch++) {
             if (s->dba_mode[ch] == DBA_NEW) {
-                s->dba_nsegs[ch] = get_bits(gbc, 3);
-                for (seg = 0; seg <= s->dba_nsegs[ch]; seg++) {
+                s->dba_nsegs[ch] = get_bits(gbc, 3) + 1;
+                for (seg = 0; seg < s->dba_nsegs[ch]; seg++) {
                     s->dba_offsets[ch][seg] = get_bits(gbc, 5);
                     s->dba_lengths[ch][seg] = get_bits(gbc, 4);
-                    s->dba_values[ch][seg] = get_bits(gbc, 3);
+                    s->dba_values[ch][seg]  = get_bits(gbc, 3);
                 }
                 /* run last 2 bit allocation stages if new dba values */
                 bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
             }
         }
-    } else if(blk == 0) {
-        for(ch=0; ch<=s->channels; ch++) {
+    } else if (blk == 0) {
+        for (ch = 0; ch <= s->channels; ch++) {
             s->dba_mode[ch] = DBA_NONE;
         }
     }
 
     /* Bit allocation */
-    for(ch=!cpl_in_use; ch<=s->channels; ch++) {
-        if(bit_alloc_stages[ch] > 2) {
+    for (ch = !cpl_in_use; ch <= s->channels; ch++) {
+        if (bit_alloc_stages[ch] > 2) {
             /* Exponent mapping into PSD and PSD integration */
             ff_ac3_bit_alloc_calc_psd(s->dexps[ch],
                                       s->start_freq[ch], s->end_freq[ch],
                                       s->psd[ch], s->band_psd[ch]);
         }
-        if(bit_alloc_stages[ch] > 1) {
+        if (bit_alloc_stages[ch] > 1) {
             /* Compute excitation function, Compute masking curve, and
                Apply delta bit allocation */
             if (ff_ac3_bit_alloc_calc_mask(&s->bit_alloc_params, s->band_psd[ch],
-                                           s->start_freq[ch], s->end_freq[ch],
-                                           s->fast_gain[ch], (ch == s->lfe_ch),
-                                           s->dba_mode[ch], s->dba_nsegs[ch],
+                                           s->start_freq[ch],  s->end_freq[ch],
+                                           s->fast_gain[ch],   (ch == s->lfe_ch),
+                                           s->dba_mode[ch],    s->dba_nsegs[ch],
                                            s->dba_offsets[ch], s->dba_lengths[ch],
-                                           s->dba_values[ch], s->mask[ch])) {
+                                           s->dba_values[ch],  s->mask[ch])) {
                 av_log(s->avctx, AV_LOG_ERROR, "error in bit allocation\n");
-                return -1;
+                return AVERROR_INVALIDDATA;
             }
         }
-        if(bit_alloc_stages[ch] > 0) {
+        if (bit_alloc_stages[ch] > 0) {
             /* Compute bit allocation */
             const uint8_t *bap_tab = s->channel_uses_aht[ch] ?
                                      ff_eac3_hebap_tab : ff_ac3_bap_tab;
-            ff_ac3_bit_alloc_calc_bap(s->mask[ch], s->psd[ch],
+            s->ac3dsp.bit_alloc_calc_bap(s->mask[ch], s->psd[ch],
                                       s->start_freq[ch], s->end_freq[ch],
                                       s->snr_offset[ch],
                                       s->bit_alloc_params.floor,
@@ -1242,8 +1271,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     /* unused dummy data */
     if (s->skip_syntax && get_bits1(gbc)) {
         int skipl = get_bits(gbc, 9);
-        while(skipl--)
-            skip_bits(gbc, 8);
+        skip_bits_long(gbc, 8 * skipl);
     }
 
     /* unpack the transform coefficients
@@ -1253,22 +1281,23 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     /* TODO: generate enhanced coupling coordinates and uncouple */
 
     /* recover coefficients if rematrixing is in use */
-    if(s->channel_mode == AC3_CHMODE_STEREO)
+    if (s->channel_mode == AC3_CHMODE_STEREO)
         do_rematrixing(s);
 
     /* apply scaling to coefficients (headroom, dynrng) */
-    for(ch=1; ch<=s->channels; ch++) {
-        float gain = s->mul_bias / 4194304.0f;
-        if(s->channel_mode == AC3_CHMODE_DUALMONO) {
-            gain *= s->dynamic_range[2-ch];
+    for (ch = 1; ch <= s->channels; ch++) {
+        float gain = 1.0 / 4194304.0f;
+        if (s->channel_mode == AC3_CHMODE_DUALMONO) {
+            gain *= s->dynamic_range[2 - ch];
         } else {
             gain *= s->dynamic_range[0];
         }
-        s->dsp.int32_to_float_fmul_scalar(s->transform_coeffs[ch], s->fixed_coeffs[ch], gain, 256);
+        s->fmt_conv.int32_to_float_fmul_scalar(s->transform_coeffs[ch],
+                                               s->fixed_coeffs[ch], gain, 256);
     }
 
     /* apply spectral extension to high frequency bins */
-    if (s->spx_in_use) {
+    if (s->spx_in_use && CONFIG_EAC3_DECODER) {
         ff_eac3_apply_spectral_extension(s);
     }
 
@@ -1278,27 +1307,30 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     downmix_output = s->channels != s->out_channels &&
                      !((s->output_mode & AC3_OUTPUT_LFEON) &&
                      s->fbw_channels == s->out_channels);
-    if(different_transforms) {
+    if (different_transforms) {
         /* the delay samples have already been downmixed, so we upmix the delay
            samples in order to reconstruct all channels before downmixing. */
-        if(s->downmixed) {
+        if (s->downmixed) {
             s->downmixed = 0;
             ac3_upmix_delay(s);
         }
 
         do_imdct(s, s->channels);
 
-        if(downmix_output) {
-            s->dsp.ac3_downmix(s->output, s->downmix_coeffs, s->out_channels, s->fbw_channels, 256);
+        if (downmix_output) {
+            s->ac3dsp.downmix(s->outptr, s->downmix_coeffs,
+                              s->out_channels, s->fbw_channels, 256);
         }
     } else {
-        if(downmix_output) {
-            s->dsp.ac3_downmix(s->transform_coeffs+1, s->downmix_coeffs, s->out_channels, s->fbw_channels, 256);
+        if (downmix_output) {
+            s->ac3dsp.downmix(s->xcfptr + 1, s->downmix_coeffs,
+                              s->out_channels, s->fbw_channels, 256);
         }
 
-        if(downmix_output && !s->downmixed) {
+        if (downmix_output && !s->downmixed) {
             s->downmixed = 1;
-            s->dsp.ac3_downmix(s->delay, s->downmix_coeffs, s->out_channels, s->fbw_channels, 128);
+            s->ac3dsp.downmix(s->dlyptr, s->downmix_coeffs, s->out_channels,
+                              s->fbw_channels, 128);
         }
 
         do_imdct(s, s->out_channels);
@@ -1310,68 +1342,81 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
 /**
  * Decode a single AC-3 frame.
  */
-static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
-                            AVPacket *avpkt)
+static int ac3_decode_frame(AVCodecContext * avctx, void *data,
+                            int *got_frame_ptr, AVPacket *avpkt)
 {
+    AVFrame *frame     = data;
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     AC3DecodeContext *s = avctx->priv_data;
-    int16_t *out_samples = (int16_t *)data;
-    int blk, ch, err;
+    int blk, ch, err, ret;
     const uint8_t *channel_map;
     const float *output[AC3_MAX_CHANNELS];
-
-    /* initialize the GetBitContext with the start of valid AC-3 Frame */
-    if (s->input_buffer) {
-        /* copy input buffer to decoder context to avoid reading past the end
-           of the buffer, which can be caused by a damaged input stream. */
+    enum AVMatrixEncoding matrix_encoding;
+    AVDownmixInfo *downmix_info;
+
+    /* copy input buffer to decoder context to avoid reading past the end
+       of the buffer, which can be caused by a damaged input stream. */
+    if (buf_size >= 2 && AV_RB16(buf) == 0x770B) {
+        // seems to be byte-swapped AC-3
+        int cnt = FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE) >> 1;
+        s->bdsp.bswap16_buf((uint16_t *) s->input_buffer,
+                            (const uint16_t *) buf, cnt);
+    } else
         memcpy(s->input_buffer, buf, FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE));
-        init_get_bits(&s->gbc, s->input_buffer, buf_size * 8);
-    } else {
-        init_get_bits(&s->gbc, buf, buf_size * 8);
-    }
+    buf = s->input_buffer;
+    /* initialize the GetBitContext with the start of valid AC-3 Frame */
+    init_get_bits(&s->gbc, buf, buf_size * 8);
 
     /* parse the syncinfo */
-    *data_size = 0;
     err = parse_frame_header(s);
 
     if (err) {
-        switch(err) {
-            case AAC_AC3_PARSE_ERROR_SYNC:
-                av_log(avctx, AV_LOG_ERROR, "frame sync error\n");
-                return -1;
-            case AAC_AC3_PARSE_ERROR_BSID:
-                av_log(avctx, AV_LOG_ERROR, "invalid bitstream id\n");
-                break;
-            case AAC_AC3_PARSE_ERROR_SAMPLE_RATE:
-                av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
-                break;
-            case AAC_AC3_PARSE_ERROR_FRAME_SIZE:
-                av_log(avctx, AV_LOG_ERROR, "invalid frame size\n");
-                break;
-            case AAC_AC3_PARSE_ERROR_FRAME_TYPE:
-                /* skip frame if CRC is ok. otherwise use error concealment. */
-                /* TODO: add support for substreams and dependent frames */
-                if(s->frame_type == EAC3_FRAME_TYPE_DEPENDENT || s->substreamid) {
-                    av_log(avctx, AV_LOG_ERROR, "unsupported frame type : skipping frame\n");
-                    return s->frame_size;
-                } else {
-                    av_log(avctx, AV_LOG_ERROR, "invalid frame type\n");
-                }
-                break;
-            default:
-                av_log(avctx, AV_LOG_ERROR, "invalid header\n");
-                break;
+        switch (err) {
+        case AAC_AC3_PARSE_ERROR_SYNC:
+            av_log(avctx, AV_LOG_ERROR, "frame sync error\n");
+            return AVERROR_INVALIDDATA;
+        case AAC_AC3_PARSE_ERROR_BSID:
+            av_log(avctx, AV_LOG_ERROR, "invalid bitstream id\n");
+            break;
+        case AAC_AC3_PARSE_ERROR_SAMPLE_RATE:
+            av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
+            break;
+        case AAC_AC3_PARSE_ERROR_FRAME_SIZE:
+            av_log(avctx, AV_LOG_ERROR, "invalid frame size\n");
+            break;
+        case AAC_AC3_PARSE_ERROR_FRAME_TYPE:
+            /* skip frame if CRC is ok. otherwise use error concealment. */
+            /* TODO: add support for substreams and dependent frames */
+            if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT || s->substreamid) {
+                av_log(avctx, AV_LOG_DEBUG,
+                       "unsupported frame type %d: skipping frame\n",
+                       s->frame_type);
+                *got_frame_ptr = 0;
+                return buf_size;
+            } else {
+                av_log(avctx, AV_LOG_ERROR, "invalid frame type\n");
+            }
+            break;
+        case AAC_AC3_PARSE_ERROR_CRC:
+        case AAC_AC3_PARSE_ERROR_CHANNEL_CFG:
+            break;
+        default: // Normal AVERROR do not try to recover.
+            *got_frame_ptr = 0;
+            return err;
         }
     } else {
         /* check that reported frame size fits in input buffer */
         if (s->frame_size > buf_size) {
             av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");
             err = AAC_AC3_PARSE_ERROR_FRAME_SIZE;
-        } else if (avctx->error_recognition >= FF_ER_CAREFUL) {
+        } else if (avctx->err_recognition & AV_EF_CRCCHECK) {
             /* check for crc mismatch */
-            if (av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, &buf[2], s->frame_size-2)) {
+            if (av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, &buf[2],
+                       s->frame_size - 2)) {
                 av_log(avctx, AV_LOG_ERROR, "frame CRC mismatch\n");
+                if (avctx->err_recognition & AV_EF_EXPLODE)
+                    return AVERROR_INVALIDDATA;
                 err = AAC_AC3_PARSE_ERROR_CRC;
             }
         }
@@ -1380,47 +1425,137 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
     /* if frame is ok, set audio parameters */
     if (!err) {
         avctx->sample_rate = s->sample_rate;
-        avctx->bit_rate = s->bit_rate;
+        avctx->bit_rate    = s->bit_rate;
+    }
 
-        /* channel config */
+    /* channel config */
+    if (!err || (s->channels && s->out_channels != s->channels)) {
         s->out_channels = s->channels;
-        s->output_mode = s->channel_mode;
-        if(s->lfe_on)
+        s->output_mode  = s->channel_mode;
+        if (s->lfe_on)
             s->output_mode |= AC3_OUTPUT_LFEON;
-        if (avctx->request_channels > 0 && avctx->request_channels <= 2 &&
-                avctx->request_channels < s->channels) {
-            s->out_channels = avctx->request_channels;
-            s->output_mode  = avctx->request_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO;
-            s->channel_layout = ff_ac3_channel_layout_tab[s->output_mode];
+        if (s->channels > 1 &&
+            avctx->request_channel_layout == AV_CH_LAYOUT_MONO) {
+            s->out_channels = 1;
+            s->output_mode  = AC3_CHMODE_MONO;
+        } else if (s->channels > 2 &&
+                   avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
+            s->out_channels = 2;
+            s->output_mode  = AC3_CHMODE_STEREO;
         }
-        avctx->channels = s->out_channels;
-        avctx->channel_layout = s->channel_layout;
 
         /* set downmixing coefficients if needed */
-        if(s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) &&
+        if (s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) &&
                 s->fbw_channels == s->out_channels)) {
             set_downmix_coeffs(s);
         }
-    } else if (!s->out_channels) {
-        s->out_channels = avctx->channels;
-        if(s->out_channels < s->channels)
-            s->output_mode  = s->out_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO;
+    } else if (!s->channels) {
+        av_log(avctx, AV_LOG_ERROR, "unable to determine channel mode\n");
+        return AVERROR_INVALIDDATA;
+    }
+    avctx->channels = s->out_channels;
+    avctx->channel_layout = avpriv_ac3_channel_layout_tab[s->output_mode & ~AC3_OUTPUT_LFEON];
+    if (s->output_mode & AC3_OUTPUT_LFEON)
+        avctx->channel_layout |= AV_CH_LOW_FREQUENCY;
+
+    /* set audio service type based on bitstream mode for AC-3 */
+    avctx->audio_service_type = s->bitstream_mode;
+    if (s->bitstream_mode == 0x7 && s->channels > 1)
+        avctx->audio_service_type = AV_AUDIO_SERVICE_TYPE_KARAOKE;
+
+    /* get output buffer */
+    frame->nb_samples = s->num_blocks * AC3_BLOCK_SIZE;
+    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return ret;
     }
 
     /* decode the audio blocks */
     channel_map = ff_ac3_dec_channel_map[s->output_mode & ~AC3_OUTPUT_LFEON][s->lfe_on];
-    for (ch = 0; ch < s->out_channels; ch++)
-        output[ch] = s->output[channel_map[ch]];
+    for (ch = 0; ch < s->channels; ch++) {
+        if (ch < s->out_channels)
+            s->outptr[channel_map[ch]] = (float *)frame->data[ch];
+        else
+            s->outptr[ch] = s->output[ch];
+        output[ch] = s->output[ch];
+    }
     for (blk = 0; blk < s->num_blocks; blk++) {
         if (!err && decode_audio_block(s, blk)) {
             av_log(avctx, AV_LOG_ERROR, "error decoding the audio block\n");
             err = 1;
         }
-        s->dsp.float_to_int16_interleave(out_samples, output, 256, s->out_channels);
-        out_samples += 256 * s->out_channels;
+        if (err)
+            for (ch = 0; ch < s->out_channels; ch++)
+                memcpy(s->outptr[channel_map[ch]], output[ch], sizeof(**output) * AC3_BLOCK_SIZE);
+        for (ch = 0; ch < s->out_channels; ch++)
+            output[ch] = s->outptr[channel_map[ch]];
+        for (ch = 0; ch < s->out_channels; ch++)
+            s->outptr[ch] += AC3_BLOCK_SIZE;
+    }
+
+    /* keep last block for error concealment in next frame */
+    for (ch = 0; ch < s->out_channels; ch++)
+        memcpy(s->output[ch], output[ch], sizeof(**output) * AC3_BLOCK_SIZE);
+
+    /*
+     * AVMatrixEncoding
+     *
+     * Check whether the input layout is compatible, and make sure we're not
+     * downmixing (else the matrix encoding is no longer applicable).
+     */
+    matrix_encoding = AV_MATRIX_ENCODING_NONE;
+    if (s->channel_mode == AC3_CHMODE_STEREO &&
+        s->channel_mode == (s->output_mode & ~AC3_OUTPUT_LFEON)) {
+        if (s->dolby_surround_mode == AC3_DSURMOD_ON)
+            matrix_encoding = AV_MATRIX_ENCODING_DOLBY;
+        else if (s->dolby_headphone_mode == AC3_DHEADPHONMOD_ON)
+            matrix_encoding = AV_MATRIX_ENCODING_DOLBYHEADPHONE;
+    } else if (s->channel_mode >= AC3_CHMODE_2F2R &&
+               s->channel_mode == (s->output_mode & ~AC3_OUTPUT_LFEON)) {
+        switch (s->dolby_surround_ex_mode) {
+        case AC3_DSUREXMOD_ON: // EX or PLIIx
+            matrix_encoding = AV_MATRIX_ENCODING_DOLBYEX;
+            break;
+        case AC3_DSUREXMOD_PLIIZ:
+            matrix_encoding = AV_MATRIX_ENCODING_DPLIIZ;
+            break;
+        default: // not indicated or off
+            break;
+        }
     }
-    *data_size = s->num_blocks * 256 * avctx->channels * sizeof (int16_t);
-    return s->frame_size;
+    if ((ret = ff_side_data_update_matrix_encoding(frame, matrix_encoding)) < 0)
+        return ret;
+
+    /* AVDownmixInfo */
+    if ((downmix_info = av_downmix_info_update_side_data(frame))) {
+        switch (s->preferred_downmix) {
+        case AC3_DMIXMOD_LTRT:
+            downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_LTRT;
+            break;
+        case AC3_DMIXMOD_LORO:
+            downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_LORO;
+            break;
+        case AC3_DMIXMOD_DPLII:
+            downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_DPLII;
+            break;
+        default:
+            downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_UNKNOWN;
+            break;
+        }
+        downmix_info->center_mix_level        = gain_levels[s->       center_mix_level];
+        downmix_info->center_mix_level_ltrt   = gain_levels[s->  center_mix_level_ltrt];
+        downmix_info->surround_mix_level      = gain_levels[s->     surround_mix_level];
+        downmix_info->surround_mix_level_ltrt = gain_levels[s->surround_mix_level_ltrt];
+        if (s->lfe_mix_level_exists)
+            downmix_info->lfe_mix_level       = gain_levels_lfe[s->lfe_mix_level];
+        else
+            downmix_info->lfe_mix_level       = 0.0; // -inf dB
+    } else
+        return AVERROR(ENOMEM);
+
+    *got_frame_ptr = 1;
+
+    return FFMIN(buf_size, s->frame_size);
 }
 
 /**
@@ -1432,31 +1567,58 @@ static av_cold int ac3_decode_end(AVCodecContext *avctx)
     ff_mdct_end(&s->imdct_512);
     ff_mdct_end(&s->imdct_256);
 
-    av_freep(&s->input_buffer);
-
     return 0;
 }
 
-AVCodec ac3_decoder = {
-    .name = "ac3",
-    .type = CODEC_TYPE_AUDIO,
-    .id = CODEC_ID_AC3,
+#define OFFSET(x) offsetof(AC3DecodeContext, x)
+#define PAR (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM)
+static const AVOption options[] = {
+    { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },
+    { NULL},
+};
+
+static const AVClass ac3_decoder_class = {
+    .class_name = "AC3 decoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVCodec ff_ac3_decoder = {
+    .name           = "ac3",
+    .long_name      = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
+    .type           = AVMEDIA_TYPE_AUDIO,
+    .id             = AV_CODEC_ID_AC3,
     .priv_data_size = sizeof (AC3DecodeContext),
-    .init = ac3_decode_init,
-    .close = ac3_decode_end,
-    .decode = ac3_decode_frame,
-    .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
+    .init           = ac3_decode_init,
+    .close          = ac3_decode_end,
+    .decode         = ac3_decode_frame,
+    .capabilities   = AV_CODEC_CAP_DR1,
+    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
+                                                      AV_SAMPLE_FMT_NONE },
+    .priv_class     = &ac3_decoder_class,
 };
 
 #if CONFIG_EAC3_DECODER
-AVCodec eac3_decoder = {
-    .name = "eac3",
-    .type = CODEC_TYPE_AUDIO,
-    .id = CODEC_ID_EAC3,
+static const AVClass eac3_decoder_class = {
+    .class_name = "E-AC3 decoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVCodec ff_eac3_decoder = {
+    .name           = "eac3",
+    .long_name      = NULL_IF_CONFIG_SMALL("ATSC A/52B (AC-3, E-AC-3)"),
+    .type           = AVMEDIA_TYPE_AUDIO,
+    .id             = AV_CODEC_ID_EAC3,
     .priv_data_size = sizeof (AC3DecodeContext),
-    .init = ac3_decode_init,
-    .close = ac3_decode_end,
-    .decode = ac3_decode_frame,
-    .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52B (AC-3, E-AC-3)"),
+    .init           = ac3_decode_init,
+    .close          = ac3_decode_end,
+    .decode         = ac3_decode_frame,
+    .capabilities   = AV_CODEC_CAP_DR1,
+    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
+                                                      AV_SAMPLE_FMT_NONE },
+    .priv_class     = &eac3_decoder_class,
 };
 #endif